package com.jsb.gatewayservice.utils;

import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.support.spring.FastJsonRedisSerializer;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.data.redis.serializer.StringRedisSerializer;

/**
 * redis配置
 *
 * @author zmy
 * @create 2023-02-04 0:42
 */
@EnableCaching
@Configuration
public class RedisConfig extends CachingConfigurerSupport {

    @Bean
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
        RedisTemplate<Object, Object> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        FastJsonRedisSerializer<Object> fastJsonRedisSerializer = new FastJsonRedisSerializer(Object.class);
        ParserConfig.getGlobalInstance().setAutoTypeSupport(true);

        // 使用StringRedisSerializer来序列化和反序列化redis的key值
        template.setKeySerializer(new StringRedisSerializer());
        template.setValueSerializer(fastJsonRedisSerializer);
        // Hash的key也采用StringRedisSerializer的序列化方式
        template.setHashValueSerializer(fastJsonRedisSerializer);
        template.setHashKeySerializer(new StringRedisSerializer());

        template.afterPropertiesSet();
        return template;
    }

    @Bean
    public DefaultRedisScript<Long> limitScript() {
        DefaultRedisScript<Long> redisScript = new DefaultRedisScript<>();
        redisScript.setScriptText(limitScriptText());
        redisScript.setResultType(Long.class);
        return redisScript;
    }

    /**
     * 限流脚本
     */
    private String limitScriptText() {
        return "local key = KEYS[1]\n" +
                "local count = tonumber(ARGV[1])\n" +
                "local time = tonumber(ARGV[2])\n" +
                "local current = redis.call('get', key);\n" +
                "if current and tonumber(current) > count then\n" +
                "    return tonumber(current);\n" +
                "end\n" +
                "current = redis.call('incr', key)\n" +
                "if tonumber(current) == 1 then\n" +
                "    redis.call('expire', key, time)\n" +
                "end\n" +
                "return tonumber(current);";
    }

}
